The present disclosure relates to a display unit for displaying images, an image processing device and a display method that are in use for such a display unit, and an electronic apparatus that includes such a display unit.
In recent years, a substitution of a liquid crystal display unit or an organic EL (Electro-Luminescence) display unit for a CRT (Cathode Ray Tube) display unit has been progressing. Such a display unit has been becoming the mainstream of a display unit because of its capability to reduce power consumption as well as to configure a low-profile display unit as compared with the CRT display unit.
In a display unit, high image quality is typically desired. One of various factors for determining the image quality is the contrast. For example, Japanese Patent No. 4293747 discloses an organic EL display unit that achieves high contrast and suppresses any overcurrent in organic EL display elements, wherein each pixel is configured of three sub-pixels of red (R), green (G), and blue (B). In this display unit, for example, a current flowing through all the pixels (total pixel current) is detected, and a control is carried out in a manner of decreasing a pixel luminescence time in the case of the large total pixel current, and increasing the pixel luminescence time in the case of the small total pixel current. In such a manner, for example, when the light-emitting area is small on a display screen, the total pixel current is small, and thus a control is carried out to increase a luminescence period of time, thereby achieving high contrast. On the other hand, for example, when the light-emitting area is large on a display screen, the total pixel current is large, and thus a control is carried out to decrease the luminescence period of time, thereby suppressing any overcurrent in organic EL display elements.
Meanwhile, there may be some display units in which each pixel is composed of four sub-pixels. For example, Japanese Patent No. 4434935 discloses an organic EL display unit that reduces power consumption in such a manner that each pixel is configured of sub-pixels of red (R), green (G), blue (B), and white (W). In this display unit, for example, when a white color is to be displayed, power consumption is reduced by making a sub-pixel of white (W) luminescent mainly instead of, for example, three sub-pixels of red (R), green (G), and blue (B).